Illuminating device for bake-ovens.



PATENTED JULY21, 1908.

G. N. BERGMANN. ILLUMINATING DEVICE FOR BAKE OVENS.

APPLICATION FILED DEG.14,1907.

III-

UNITED STATES PATENT OFFICE.

CHRISTIAN N. BERGMANN, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TOWARD-MAOKEY COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

ILLUMINA'IING DEVICE FOR BAKE-OVENS.

Specification of Letters Patent.

Patented July 21, 1908.

Application filed December 14, 1907. Serial No. 406,511.

To all whom it may concern:

Be it known that I, CHRISTIAN N. BERG- MANN, acitizen of the UnitedStates, residing at Pittsburg, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inIlluminating Devices for Bake-Ovens, of which the following is aspecification, reference .being had therein to the accompanying drawing.

My invention refers to improvements in bake-ovens or similar apparatusand is designed for the purpose of roviding automatically operativemeans for lighting the interior of the oven actuated by the opening ofthe door to close the circuit to a lamp so located as to illuminate theinterior of the oven and to break the circuit automatically upon closingof the door as shall be more fully hereinafter described.

Referring to the drawingsFigure 1 is a view in front elevation of anoven provided with my improvement. Fig. 2 is a horizontal sectional viewindicated by the line II, II of Fig. 1. Fig. 3 is a vertical sectionalView on an enlarged scale indicated by the line III, III of Fig. 1. Fig.4 is a face view in elevation of the current making and breaking switch.

2 represents the front wall of the oven, or of any chamber the interiorof which it is de sired to illuminate, preferably provided with a doorframe 3 of any suitable construction in which is hung by any suitablehinge oints 4, the swinging door 5.

6 represents the hinge rod or shaft of the door mounted in suitablehinge bearings within the frame 3 and so connected with the door thatthe shaft and door will necessarily move together. In the constructionshown, the door normally occupies the position shown in Fig. 3 whenclosed, resting downwardly upon the floor plate of the oven or frame,opening inwardly in the direction of the arrow to a raised position,indicated in dotted lines, for insertion or removal of the contents. Thehinge shaft 6 is preferably provided at one end with an operating lever7 having a balancing counterweight 8 for facilitating the manipulationof the door, the front wall or frame 3-being provided if desired with asuitable cavity 9 as shown for containing such parts. At the other sideof the door, (or at the same side of the door as is provided with theoperating lever, if preferred,) preferably within a similar receivingcavity 10, is located the automatically-operative circuit making andbreaking mechanism, which is constructed as follows: One or more lamps11 are located in the interior of the oven at any suitable point forgood illumination and are connected by circuit wires with attachingbinding post terminals 12 and 13 mounted on an insulating base 14.

15 is a lever pivoted at 16 and in electrical communication with bindingpost terminal '13, provided at one end with a contacting make-and-breakterminal 17 and at the other end with an overbalancing counterweight 18,adapted to normally hold terminal 17 in electrical contact with abearing abutment or flange 19 of binding post terminal 12.

The end of the hinge shaft 6 projects into proximity with thecounterweighted end of lever 15 and is provided with a projecting arm orlug 20, integral with or secured to the shaft, adapted to swing upunderneath the counterweighted end of frame 15, when the oven door islowered as in Fig. 3, thereby lowering terminal 17 away from contactwith bearing 19, and to be depressed below said arm '15 when the door isopen as indicated in dotted lines in Fig. 3 (when illumination isdesired) permitting the counterweighted end of lever 15 to fall andterminal 17 to make circuit-closing contact with bearing 1.9 toestablish a current through the lamp.

At the point on lever 15 where arm 20 engages underneath it, it isprovided with an insulated contact bearing 21 and intervenmg insulation22, thereby preventing short circuit through the lever, as Will bereadily understood.

It will be obvious that the contacting if mechanism may be changed orvaried by the skilled mechanic over the construction shown anddescribed, the form utilized in the present application being one whichI have used successfully in practice, but all such changesor variationsin its detailed construction are to be considered as within the scope ofthe following claims.

Having described my invention, what I claim and desire to secure byLetters Patent, 1s

1. The combination with a bake oven pro vided with an electric lamparranged to illuminate its interior, of two attaching elements adaptedto be connected to close the circuit through the lamp, a lever pivotallymounted on one of said elements having a counterweight at one end and anabutting makeand-break terminal at the other end adapted to bear againsta portion of the other element by the gravity of said counter-weight,and an opening and closing door provided with a hinge rod having an armarranged to engage underneath the counter-weighted end of said lever tolower its make-and-break terminal from contact with said element whenthe oven door is closed, to break the circuit, substantially as setforth.

2. The combination with a bake oven provided with an electric lamparranged to illuminate its interior, of two attaching elements adaptedto be connected to close the circuit through the lamp, a lever pivotallymounted on one of said elements having a counterweight at one end and anabutting make-andbreak terminal at the other end adapted to bear againsta portion of the other element by the gravity of saidcounter-weight,a11d an opening and closing door provided with a hingerod having an arm arranged to engage underneath the counter-weighted endof said lever to lower its make-and-break terminal from contact withsaid element when the oven door is closed, to break the circuit, saidcounter-weighted lever having an insulating cover at its point ofcontact with the hinge rod arm, substantially as set forth.

In testimony whereof I afhx my signature in presence of two witnesses.

CHRISTIAN N. BERGMANN.

Vitnesses:

C. M. CLARKE, CHAS. S. LEPLEY.

